‘GEMINI” is a gelato of a play for a hot summer day, a delicious summer refreshment.The 1976 comedy by Albert Innaurato about Italian-Americans and other ethnics in South Philly is getting, at Second Stage, an ideal production under the smart hand of director Mark Brokaw.

Brokaw’s a genius at finding the rhythms of a piece, its moments of mad pace and of quiet space, and at finding just the right actors to express them.

Two near-identical, two-story, fake-brick houses in South Philly in the late spring of 1973 give onto bare backyards. Riccardo Hernandez’s two-house set – a feature of Italian comedy right back to Plautus – promises a lot of coming and going, confusion and hysteria, and we get our share, but basically Innaurato is interested less in incident than in character.

The play abounds in sad encounters between unlikely characters, which are also hilarious. Chekhov meets Groucho.

The central character – clearly, the author figure – is Francis Geminiani, home from Harvard for the summer and just about to turn 21. Francis, played with adorably galumphy earnestness by Brian Mysliwy, is a shy guy, a loner who spends a lot of time up in his room listening to Maria Callas.

His divorced dad, Fran, is a salt-of-the-earth, working-class man who dates Lucille, a finicky, eccentric neighborhood widow. Transcending all the “goombah” cliches, Joseph Siravo is wonderful as the father, who pretty much gets the picture about his son but is afraid to ask.

What Julie Boyd does with Lucille is a class in comedy and economy. It’s a gem of a job.

As often, the action is started by the arrival of visitors. Two of Francis’ Harvard friends, a sister-brother pair called Judith and Randy Hastings, have hitchhiked to Philly on the way to their “summer place” north of Boston. So there’s a class thing going on, as well as a sex thing.

Sarah Rafferty handles Judith well, often required to show snooty disdain at the zany goings-on. Rafferty is always appealing. And Thomas Sadoski triumphs as the naive Randy.

And then there are the next-door neighbors, Bunny Weinberger and her son Herschel. Bunny is a bawdy broad, a raucous dynamo of sexual energy who swigs Jack Daniel’s and sports high-heeled gold-striped shoes. Linda Hart wrings every ounce of comic oomph from the role but never lets us forget that this is a sad, desperate woman. Sixteen-year-old Michael Kendrick brilliantly captures the manic neediness of Herschel.

“Gemini” may be a bit rosy in its vision of warm acceptance, but such is comedy’s privilege. We realize, too, at the end that this is really a play about an artist breaking away – with love, with love – from family and neighborhood to become himself.